Method of automatically cutting out material pieces from a web in conformance with a scanned cutting pattern

ABSTRACT

A method of automatically cutting out material pieces from a web in conformance with a cutting pattern including scanning a line of predetermined width defining a pattern cutting line, orienting a sensor arrangement along at least one edge of the line, or centrally thereof, transmitting a signal from the sensor arrangement to a control device in dependance upon the intensity of the signal received, and actuating a cutting knife for cutting the material web pursuant to the evaluation of the sensor signal.

United States Patent [191 Stumpf May 6, 1975 [54] METHOD OFAUTOMATICALLY CUTTING 3,470,780 lO/l969 Wright 83/925 CC O M ER PIECESFROM A WEB IN 3,626,799 l2/l97l Gerber 83/925 CC 3,766,813 l0/l973 83/56CONFORMANCE WITH A SCANNED CUTTING PATTERN Giinter Otto Stumpf, 7421Mehrstetten, Kreis Munsingen, Germany Filed: June 13, 1973 Appl. No.:369,760

lnventor:

Foreign Application Priority Data Mueller 83/56 Primary Examiner-J. M.Meister [57] ABSTRACT A method of automatically cutting out materialpieces from a web in conformance with a cutting pattern includingscanning a line of predetermined width defining a pattern cutting line,orienting a sensor arrangement along at least one edge of the line, orcentrally thereof, transmitting a signal from the sensor arrangement toa control device in dependance upon the intensity of the signalreceived, and actuating a cutting knife for cutting the material webpursuant to the evaluation of the sensor signal.

2 Claims, 11 Drawing Figures Y IU'HEU 5 3.881.379

SHEET REF 5 FIELD OF THE INVENTION The present invention relates to amethod for the automatic cutting out of material components or piecesfrom a material web pursuant to a cutting pattern.

DISCUSSION OF THE PRIOR ART A method for the cutting out of material orcloth pieces from a web is generally known from German Pat. No.1,256,173. Thus, in the prior art method, the pattern of cutting isresolved by an uninterrupted or, in effect, noncrossing line. This, inactuality, signifies that the various line portions neither contact norcross each other at any point. Consequently, two pieces of the cuttingpattern are at all times interconnected by two closely extending lineportions, which encompass therebetween a connecting portion or bridgewhich, after the cutting out of the cutting pattern, must be cut throughso as to provide for separation of the individual material pieces. Theseparation of the connecting portion between the two material pieces iseffected through a manual operation. This, of course, creates thedrawback, that a manual operation follows the previous fully automaticcutting method, which partly detracts from the high degree ofautomation. Additionally, the connecting portion remains attached to oneof the two material pieces which are interconnected by means of thatparticular connecting portion, since the separation between the piecesis only effected by means of a single cut through the connectingportion. Consequently, in order to provide for the clean cutting out ofthe material pieces and to separate the latter, it is required to carryout two manual cutting operations so as to completely remove theconnecting portion.

According to US. Pat. Nos. 1,774,865 and 2,172,3 l3 it is generallyknown that in order to obtain the precise sensing and separation ofmaterial pieces from a continuous material web, a photosensing orscanning device may be provided in which a sensor arrangement is adaptedto be oriented adjacent the edge of the cutting or separating line.However, even applying the concepts of the above-mentioned US. patentstoward effecting the cutting operation disclosed in German Pat. No.1,256,] 73 still would not provide a fully automatic method of cuttingout material pieces from a material web.

SUMMARY OF THE INVENTION It is, accordingly, a primary object of thepresent invention to provide a novel and improved method for the fullyautomatic cutting out of completely separated material pieces from amaterial web.

Another object of the present invention is to provide a novel andimproved method for the fully automatic cutting out of completelyseparated material pieces from a material web which completelyeliminates the need for the subsequent removal of any material portionsbetween the material pieces.

A further object of the present invention lies in providing a method asdescribed above which utilizes a scanning arrangement in which aphotosensor is conveyed along an edge of the separating line so as toallow for the fully automatic cutting out and separation of the materialpieces.

BRIEF DESCRIPTION OF THE DRAWINGS Reference may now be had to thefollowing detailed description of a method and arrangement for carryingout the present invention, illustrating various exemplary embodiments,and taken in conjunction with the accompanying drawings, in which:

FIG. 1 illustrates a simple form of a cutting pattern with threematerial pieces;

FIG. 2 illustrates the linear guide path used for resolving the cuttingpattern of FIG. I pursuant to a first embodiment;

FIG. 3 illustrates the linear guide path used for resolving the cuttingpattern of FIG. 1 pursuant to a second embodiment;

FIG. 4 illustrates a variation of the linear guide path for effectingthe cutting pattern according to FIG. 1 in accordance with the secondembodiment;

FIG. 5 illustrates a perspective, generally schematic view of anarrangement for carrying out the inventive method;

FIG. 6 illustrates, on an enlarged scale, a generally schematicrepresentation of a scanning head utilized in the arrangement of FIG. 5;

FIG. 7 is an enlarged fragmentary representation of the region VIIshowing the scanning along an edge of the line in FIG. 2;

FIG. 8 is an enlarged fragmentary representation of the region VIIIshowing the scanning of both edges of the line in FIG. 4;

FIG. 9 illustrates a representative realistic material cutting pattern;

FIG. 10 illustrates the linear cutting guide path for the separation ofthe material pieces according to the pattern of FIG. 9, employing thefirst embodiment of cutting pattern; and

FIG. 11 shows the linear cutting guide path for the separation of thematerial pieces according to the pattern of FIG. 9, employing the secondembodiment of cutting pattern.

DETAILED DESCRIPTION Referring now in detail to the drawings, FIG. 1illustrates a simplified cutting pattern having a cutting pattern baseportion 1 and three cutting pieces, 2, 3 and 4. In accordance with thiscutting pattern, pieces may be cut out from one or more superimposedlayers of material webs. The cutting pattern may have a somewhat smallerphysical measurement as compared to the actual material pieces which areto be cut out. In this instance, a suitable scale transfer or conversionmeans must be provided intermediate the scanning arrangement and theinstallation for the cutting out of the material pieces.

The aggregate material pieces 2, 3 and 4 of the cutting pattern are cutout by means of a single, continuous cut. This signifies that thecutting pattern must be resolved in an uninterrupted line which extendsabout the edges of all of the material pieces 2, 3 and 4. In thismanner, the pieces are to be completely separated from each other afterthe completion of the single cutting sequence.

A first application for the separation of the cutting pattern accordingto FIG. I by means of an interrupted line Sis illustrated in FIG. 2. Inthat instance, the pieces 2 and 4 are connected to each other by twoline portions 6 and 7 which for a short distance extend in a coincidingrelationship. Similarly, the two pieces 2 and 3 are connected to eachother by two line portions which extend over a short distance in acoinciding relationship. At the location in which the line portions 6and 7 are superimposed or coincide, there is effected the separation ofthe pieces from the material layers by means of a cutting knife.

Another possiblity for the guidance of line is illustrated in FIG. 3. Inthis instance. the material pieces 3 and 4 are also connected to eachother by two lines portions 8 and 9 which cross at locations 10 and I].At the crossing locations 10 and 11 there is effected the separation ofthe pieces which are cut out of the material layers in conformance withthe pieces 3 and 4 of the cutting pattern.

Due to reasons requiring further explanation, the corners in FIGS. 2 and3 must be rounded. However, if it is desired that the corners be made aspointed as is possible, then line 5, in accordance with FIG. 4, may beconveyed toward the corner points in a path so as to describe a loop. Onthe basis of loop 12 and the crossing points 13 in FIG. 4, it may beascertained that the loop deviates from the corresponding piece 3 of thecutting pattern.

The arrangement illustrated in FIG. 5 of the drawings includes twotables 19 and 20. The cutting pattern which is to be scanned ispositioned on table 19, while the material layers are positioned ontable 20, from which material pieces are to be cut in conformance withthe pattern pieces of the cutting pattern. The cutting pattern and thematerial layers are not illustrated. A pair of longitudinal guides 21are mounted on table 20, having positioned thereon a pair of runningframes 22 which are interconnected by a traverse 23. A suitable drive24, which is not described in greater detail, is located on one of therunning frames 22. The drive 24 is adapted to convey the running frames,on the one hand, in the direction of the longitudinal guides 21, and mayfurther be connected with a spindle 25. The spindle 25 is connected to across-slide 26 which is slidably mounted on the traverse 23. Thecross-slide 26 supports a cutting knife 27 which is verticallyreciprocable by means of a cutting motor 28. Furthermore, crossslide 26supports thereon a rotary motor 29 which imparts a predetermined cuttingdirection to the cutting knife 27. Furthermore, a transverse projectingarm 32 is seated on one of the running frames 22, on which a scanningdevice 30 is slidably supported. The scanning device 30 is alsoconnected to spindle 25 and, consequently, is slidable in synchronousmotion with the cross-slide 26. The scanning device 30 is provided onits lower surface with a sensing head 31. A switch or control panel isdesignated by reference numeral 34.

The sensing head 31 is generally schematically illustrated in FIG. 6 ofthe drawings. A photometer 40 is located in the sensing head 31 which isadapted to scan a portion of the area of the cutting pattern 1 throughthe intermediary of an optical installation 35. The optical installation35 is rotatable about a vertical axis within the sensing head. A lamp 36is connected with the optical installation, and is adapted to direct alight spot onto the cutting pattern I, which is larger than the scannedpattern area. The lamp 36 is pivotable about the rotational axis of theoptical installation 35 in conjunction with the latter. Furthermore, theoptical installation 35 includes a follower wheel 37, which is alsopivotable about the axis together with the optical installation 35. Theangle of rotation of the optical installation is transmitted, by meansof gear wheels 38 and 39, to a rotation indicator 4!. The direction ofmovement of the sensing head 31 is represented by means of the arrow.

In FIG. 7 of the drawing, a portion of line 5 is illustrated on anenlarged scale. The light spot which is directed onto the cuttingpattern by the lamp 36 of the sensing head is designated by referencenumeral 14. The pattern portion which is scanned by the opticalarrangement 35 and photometer 40 is designated by reference numeral 15.One-half of the illuminated portion 15 is located on line 5, and theother half thereof on the cutting pattern base 1. Since the line 5 isdarker than the cutting pattern base 1, less light is reflected from thehalf of the portion 15 which is located on line 5 then from the halflocated on the cutting pattern base 1. However, the photometer 40measures the total quantity of the light which is reflected from bothhalves of the portion 15. This signifies that more light is reflectedfrom the portion 15 when the portion 15 in FIG. 7 moves toward the left;and correspondingly less light is reflected when the portion 15oppositely thereto moves toward the right. Consequently, the intensityof the reflected light measured by the photometer 40 provides a measureof the deviation of the scanned portion 15 from the left edge of line 5in FIG. 7. The intensity may, accordingly, be utilized in a known mannerfor the guidance of sensing head 31, so that the latter is orientedpursuant to the pertinent edge of line 5.

In FIG. 5, chain-dotted lines schematically illustrate where areutilized the obtained informations rotation angle" or reflected lightintensity which are transmitted from sensing head 31. Both informationsare transmitted into an evaluation installation 33, which controls thetransverse and longitudinal drive 24. The rotational angle serves toprovide correlation between the transverse direction and thelongitudinal direction of the drive, and both co-ordinates of thecutting pattern. In addition thereto, the rotational angle istransmitted to the motor 29 for determining the cutting angle of knife27. The arrangement which is schematically illustrated in FIG. 5 of thedrawings automatically moves with sensing head 31 along line 5. Needlessto say, knife 27 also cuts the corresponding material pieces out of thematerial layers on the table.

As previously mentioned, according to FIG. 6, the sensing head orientsitself only along one edge of line 5. This type of scanning is suitablewhen it is desired to follow line 5 in accordance with FIG. 2. Thisindicates that this scanning arrangement may also be utilized in cuttingpatterns in which two line portions extend in superimposed or coincidingrelationship. However, in order to provide for that the scanned portion15 (FIG. 7) lies with one-half thereof on line 5 and with the other halfthereof on the cutting pattern base 1, the line 5 in the area of thecoinciding line portions must be so extended, whereby the line edge onwhich the sensing head orients itself, at both line portions lies attimes on the other line edge of the deviating line portion. Thisindicates, for example in the instance of FIG. 2, that in at lineportion 6 the mentioned line edge lies toward the left, and at the lineportion 7 the mentioned line edge lies toward the right. When it isassumed that one moves in conjunction with the sensing head, then thementioned line edge naturally lies at both line portions 6 and 7 on thesame side, namely toward the left. Since the sensing head 31 andsimilarly other types of sensors cannot be conducted through sharpcorners, it is also a requirement that the line 5 in FIG. 2 is soguided, so that the later scanned line portion 7 approaches thepreviously scanned line portion 6 at a narrowing acute angle, until thelater scanned line portion 7 tangentially contacts the previouslyscanned line portion 6. For the same reasons also the edges of pieces 2,3 and 4 in FIG. 2 are rounded off.

In order to scan the line 5 of the cutting pattern in accordance withFIG. 4, a method is utilized pursuant to FIG. 8. For this method, thesensing head 31 illustrated in FIG. 6 is so modified whereby, in lieu ofa photometer 40 with its associated optical installation 35, there areprovided two adjacent positioned photometers with corresponding opticalinstallations. In FIG. 8 there is, needless to say, provided a lightspot 16 which is projected by lamp 36 onto the cutting pattern, and inwhich both scanned areas or portions are designated by 17 and 18. Theevaluation of the two portions 17 and 18 is separately effected. Inorder to provide for the actuation of the sensing head 31, both measuredlight intensities are compared with each other. When both of theintensities are equal then the sensing installation 31 moves along thecenter of line 5. If the light intensities become unequal, then thesensing head is actuated so that the intensities again become equal. Therotational angle is also here transmitted by the follower wheel 37.

The scanning arrangement disclosed in FIG. 8 has the advantage in thatit only concerns itself with the relative relationship of the reflectedlight intensities from both scanned portions 17 and 18. This renders itpossible to effect that a line crossing-over may be traversed by thesensing head 31, as is illustrated in FIGS. 3 and 4. In order to provideundisturbed scanning, the crossing-over angle should be approximately90.

While there has been shown what is considered to be the preferredembodiment of the invention, it will be obvious that modifications maybe made which come within the scope of the disclosure of thespecification.

What is claimed is:

l. A method of automatically cutting out material pieces from a materialweb in conformance with a cutting pattern of pattern segments, saidcutting pattern being formed by a continuous line of predeterminedwidth, comprising; automatically scanning said line with a sensorarrangement sensitive to distinctions between said line and thebackground of said cutting pattern; transmitting a signal generated inresponse to sensed distinctions to a control installation; and impartinga cutting movement to a cutting tool for said material in conformancewith the signal received by said control installation, said continuousline having portions extending between at least two adjacent patternsegments of said cutting pattern and being in coincident or crossingrelationship in at least one location, said sensor arrangement includingphoto scanning means, conveying said photo scanning means along thecenter of said line in an oriented relationship with reference to bothedges of said line, said line having a portion extending between atleast two pattern segments of said cutting pattern in crossoverconfiguration at a crossing angle of about and forming corners on saidpattern segments through the crossing point of a loop formed in saidline, said loop extending away from said pattern segment.

2. A method of automatically cutting out material pieces from a materialweb in conformance with a cutting pattern of pattern segments, saidcutting pattern being formed by a continuous line of predeterminedwidth, comprising; automatically scanning said line with a sensorarrangement sensitive to distinctions between said line and thebackground of said cutting pattern; transmitting a signal generated inresponse to sensed distinctions to a control installation; and impartinga cutting movement to a cutting tool for said material in conformancewith the signal received by said control installation, said continuousline having portions extending between at least two adjacent patternsegments of said cutting pattern and being in coincident or crossingrelationship in at least one location, said sensor arrangement includingphoto scanning means, comprising conveying said photo scanning meansalong the center of said line in an oriented relationship with referenceto both edges of said line, said line having a portion extending betweenat least two pattern segments of said cutting pattern in cross-overconfiguration at a crossing angle of about 90, said line having adarker-lighter coloring in contrast with the background of said cuttingpattern, directing at least one light spot toward both edges of the linefor photo scanning; said light spot illuminating an area of said lineand the areas of the adjacent cutting pattern background on both sidesthereof; evaluating independently the intensities of light reflectedfrom each of the line edge areas and adjacent cutting pattern backgroundareas and in the direction of scanning movement, the continuing scanningbeing moved toward the left upon the reflected light at the left sidehaving a lower intensity than the reflected light intensity at the rightside and conversely.

1. A method of automatically cutting out material pieces from a materialweb in conformance with a cutting pattern of pattern segments, saidcutting pattern being formed by a continuous line of predeterminedwidth, comprising; automatically scanning said line with a sensorarrangement sensitive to distinctions between said line and thebackground of said cutting pattern; transmitting a signal generated inresponse to sensed distinctions to a control installation; and impartinga cutting movement to a cutting tool for said material in conformancewith the signal received by said control installation, said continuousline having portions extending between at least two adjacent patternsegments of said cutting pattern and being in coincident or crossingrelationship in at least one location, said sensor arrangement includingphoto scanning means, conveying said photo scanning means along thecenter of said line in an oriented relationship with reference to bothedges of said line, said line having a portion extending between atleast two pattern segments of said cutting pattern in crossoverconfiguration at a crossing angle of about 90*, and forming corners onsaid pattern segments through the crossing point of a loop formed insaid line, said loop extending away from said pattern segment.
 2. Amethod of automatically cutting out material pieces from a material webin conformance with a cutting pattern of pattern segments, said cuttingpattern being formed by a continuous line of predetermined width,comprising; automatically scanning said line with a sensor arrangementsensitive to distinctions between said line and the background of saidcutting pattern; transmitting a signal generated in response to senseddistinctions to a control installation; and imparting a cutting movementto a cutting tool for said material in conformance with the signalreceived by said control installation, said continuous line havingportions extending between at least two adjacent pattern segments ofsaid cutting pattern and being in coincident or crossing relationship inat least one location, said sensor arrangement including photo scanningmeans, comprising conveying said photo scanning means along the centerof said line in an oriented relationship with reference to both edges ofsaid line, said line having a portion extending between at least twopattern segments of said cutting pattern in cross-over configuration ata crossing angle of about 90*, said line having a darker-lightercoloring in contrast with the background of said cutting pattern,directing at least one light spot toward both edges of the line forphoto scanning; said light spot illuminating an area of said line andthe areas of the adjacent cutting pattern background on both sidesthereof; evaluating independently the intensities of light reflectedfrom each of the line edge areas and adjacent cutting pattern backgroundareas and in the direction of scanning movement, the continuing scanningbeing moved toward the left upon the reflected light at the left sidehaving a lower intensity than the reflected light intensity at the rightside and conversely.